Electric water-heater.



PATENTED MAY l2, 1908.

0. JOHNSON.

ELECTRIC WATER HEATER.

APPLICATION FILED DBG. 29. 1905.

Figi- INVENTOR. caf 7a/7776017.

ITNESVSES.

OSCAR JOHNSON, OF SEATTLE, WASHINGTON.

i y ELECTRIC WATER-HEATER.

Specification of Letters Patent.

Patented May 12, 1908.

Application led December 29, 1905. Serial No. 293,771.

vTo all whom it may concern:

Be it known that I, OSCAR JOHNSON, a citizen of the United States, and resident of the city of- Seattle, in the oountyof King and State of Washington, have invented certain new and useful Improvements in Electric Water-Heaters, of which thefollowing is a specification.

My invention relates to an improvement in electrical water heaters, and comprises the novel parts and combinations of parts hereinafter particularly pointed out in the claims.

The object of my invention is to improve and simplify such devices.

In thev drawings I have shown my invention embodied in the form now preferredby Figure 1 is a longitudinal section of my device. Fi 2 is a p an view of the lower head showing t e water and electrical connections.4

In the form of electrical water heaters which employ a wire or like device as the resistance medium, if the current is turned on before the Wire is immersed in the liquid the wire is liable t be burned out. y

One object of my invention is to produce a heater in which there is no danger of burning out from such .a cause. The means employed by me secures this result in two Ways; first by making the water the resistance medium; second, which is related to the first, by

having the circuit normally broken and automatlcally closing it by the inlowing water.

As pole ieces I employ metal of such large size that t ere is no danger of its burning out or being injured by any current which it is possible to use, and pass the water to beheated between them, the opposite pole pieces being normally insulated from each other and the circuit being closed by' the water between them.

The form of pole pieces preferred by me consists of a series of nested tubes, 2, 3, 4 and 5, as shown in Fig. 1.l To hold these in place, I employ heads 6 and 7 which lare provided with grooves 16 adapted to receive the ends of the tubes. These tubes or pole pieces, where more than two orused, are grouped in pairs designed for connection withop osite sides of an electrical circuit. 4The eads should insulate these tubes, Or at least those of anyy pair.

The tubes of each pair constitute ole pieces for an open circuit which is close by the water whlch is passed between them.

The water therefore actsas the resistance .lar spaces between the tubes medium and not the pole pieces. The latter are of such a size and conductive capacity that the current will not heat them directly.

The heating is caused by the resistance ofthe water.

. AThe heads 6 and 7 are either of an insulating material or provided with means whereby the various tubes of each pair are insulated from each other. I have shown these heads as made of lass and provided with packing rings or was ers in the bottom of the grooves receiving the vtube ends. I have also shown means for electrically connecting the tubes of all the pairs in two sets corres onding to positive and negative poles.

he means shown consists of two wires 10, 10 embedded in the glass and connecting corresponding tubes of each pair. Binding posts 11 for the atachment of the supply Wires are connected,'one to each group.

One of the heads, as the lowerhead 6, is

provided with passages 12, through whichwater may pass from one set of tubes to the other. This head has a section which is thicker than the remainder, bounded by the dotted line 9 of Fig. 2, in which is located the binding poles 11, and the connecting wires 10.

A cap 8 outside of the head 6 fits over ay shoulder on the head and forms a chamber which connects the holes 12 which pass through the head, connecting with the annuof each pair The s ace between the tubes 3 and 4 is designed9 as an insulatingl space and may contain only air, or any suitable insulating substance. The other head 7 should be insulating in the same way as the head 6, but has no water passages except to connect with the space between the tubes of the outer set, 4 and 5.` The outer tube 5 is made lon er than the others, and the head 7 its wit in this but is provided with peripheral notches permitting free passage of the water.

The water supply ipe 1 passes through both heads 6 and 7 an 1s threaded lto receive clamping Vnuts 14, 15 which bind the whole together.. Pipe 1 is provided with openings 24 for the escape ofthe water, and pi e 2 has similar openings 23 near one end. i T e head 8 is preferably covered by an insulating disk 20 and a finishing ca 21 of metal, and a packing washer 25 is p aced beneath the nutplaced` be-k 14. packing washer 22 is also neath the, nut 15. The pipe 1 is stopped at its'` upper end by a plug 26. v

Secured to the upper projecting-end ofthe loofl pipe l is an extension 27 having holes 28 through which water may flow Jfrom the receiving chamber 29. A cap 30, preferably of insulating material, as glass, covers the extended end of tube 5 and is held down by nut.

erties against both heat and electricity, as asbestos. y

In using my device the lower pipe 38 is connected with the water supply and the binding posts 11, 11 connected with a source of electro motive force. The order of making this connection is immaterial as the circuit remains o en until water has connected the poles and t e energy of the current is operatlve to produce heat only upon the water. This heater may be used upon currents 'of different voltages and also upon either direct or alternating currents.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. An electrical liquid heater having a series of nested tubes rouped in airs, means connectin the annu ar spaces etween the tubes of t e pairs to constitute a liquid conducting passage, and means for forming opposite electrical connections with the respective tubes of the pairs.

2. An electrical liquid heater having a series of nested tubes grouped in pairs of successive tubes, the spaces between the tubes .of the pairs constituting liquid conducting passages, and the spacesl between the pairs constituting insulation.

3. An electrical liquid 'heater having a series of nested tubes grouped in airs, means for sup lyin liquid to the annu ar space bctween t e tu es of the pair at one end of the series, means for conducting liquid from the annular spaces between the tubes of the pair at the other end of the series,'means for connecting the spaces between the tubes of the different pairs to form a continuous water conducting passa e, and means for connecting the tubes of t e pairs respectively to opposite sides of an electrical circuit.

4. An electrical liquid heater having a plurality of airs of tubes nested within each other to orm annular spaces between successive tubes, each tube being insulated from its adjoining tubes, means for connecting the spaces between the tubes of the different pairs in series, water supply and discharge connections with said spaces at opposite ends of the series, and means for connecting opposite phases of an electrical current with the respective tubes of the airs.

5. An electrical-li ui heater having a plurality of pairs of tu es nested within each other to form annular spaces, insulating heads for said tubes provided with liquid conducting passages adapted to connect the spaces between the tubes of the different pairs, and means for connecting the corres onding tubes of each pair with its respective side of an open circuit.

6. An electrical liquid heater having nested tubes, insulatin heads having grooves for receiving said tu es and supportin them vapart from each other, one of sald hea s having passages permitting flow of liquid from the space between one pair of the tubes to the space between another pair of tubes, and means for connecting the tubes of each pair to constitute opposite pole pieces of an open circuit.

7. 'An electrical liquid heater having nested tubes grouped in pairs, insulating heads for the ends of the tubes sup ortinv'thein apart from each other, liquic conducting means connectinfJr the annular spaces between the tubes ol? the different airs to form a continuous passage thereof, a iquid su ply tube extending through and projecting rom both heads and the innermost of the other tubes and provided with means for clamping said heads upon the other tubes, said sup ly tube and the innermost of the other tubes having connectin liquid passages, said su ply tube being p ugged near one head; tliie outermost of txhe nested tubes projectingbeyoud this head, a cap covering this tube and forming a discharge chamber which is connected with the liquid passage of the outcrmost pair of tubes, the central supply and clamplng tube having an extension connecting with the discharge chamber and extendthrough'the outer cap to constitute a liqui dischar e, and means for connecting the tubes of eac pair to constitute opposite pole pieces of a circuit.

8. An electrical heater having nested tubular pole pieces and electrical connections thereto, heads engaging the ends of said pole pieces to-hold them together, and a su pl and discharge pipe extending through hot 1 heads and within the nested tubes and provided with means for holding the heads upon the tubular pole pieces and with supply and discharge openings, and a plug between said openings.

In testimony whereof, I have hereunto afiixed my signature in the presence of 'two witnesses. i

' OSCAR JOHNSON. Witnesses:

H. L. REYNOLDS, W. L. COLLIER. 

